Add contrib drf readme js snipped (picture source)

[SebastianKapunkt]

This adds a small JS snipped to the README. This snippet helps with the extraction of the wanted source set for the picture.

[codingjoe]

@SebastianKapunkt can you rebase this to the new API structure and maybe add a full React and Vue component? To the docs only, I don't intend to ship a NodeJS package ;)

[codecov[bot]]

Codecov Report

Base: 100.00% // Head: 100.00% // No change to project coverage :thumbsup:

Coverage data is based on head (690869a) compared to base (fc0d592). Patch has no changes to coverable lines.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #56   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files            9         9           
  Lines          260       260           
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  Hits           260       260           

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[codingjoe]

Thanks for your contributions @SebastianKapunkt towards the API changes. I believe the API is now much easier to navigate. I will close the PR, OK?